The Best Science Writing Online 2012

By Jennifer Ouellette

Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way we think about science— from fluids to fungi, poisons to pirates. Featuring noted authors and journalists as well as the brightest up-and-comers writing today, this collection provides a comprehensive look at the fascinating, innovative, and trailblazing scientific achievements and breakthroughs of 2011, along with elegant and thoughtprovoking new takes on favorite topics. This is the sixth anthology of online essays edited by Bora Zivkovic, the blogs editor at Scientific American, and with each new edition, Zivkovic expands his fan base and creates a surge of excitement about upcoming compilations. Now everyone's favorite collection will reach new horizons and even more readers. Guest-edited and with an introduction by the renowned science author and blogger Jennifer Ouellette, The Best Science Writing Online 2012 marries cutting-edge science with dynamic writing that will inspire us all.

• Language: English
• Publisher: Macmillan Publishers
• Release date: Sep 18, 2012
• ISBN: 9780374709853

Book preview

2

MAKE HISTORY, NOT VITAMIN C

EVA AMSEN

Does the Flap of a Butterfly’s Wings in Brazil Set Off a Tornado in Texas?

—Edward Lorenz

This is a story about a tiny molecular shift affecting war, politics, disease, agriculture, and international corporations. Like all good stories, it also contains a healthy dose of biochemistry and genetics, some pirates, and a few rodents of unusual size. The very start—the event that set everything in motion—is a genetic mutation that happened millions of years ago, but we’ll get to that. First, let’s meet the pirates.

The pirates in this story are Dutch, and they were active near the end of the sixteenth century. During this time, the Netherlands were occupied by Spain, and after a period of repression, the northern (Protestant) provinces started to fight off the Spanish. They were most successful on water. From 1568 onward, several ships received government permission to attack and plunder Spanish ships. These Watergeuzen dominated at sea, but in 1572 they captured the city of Brielle, marking a turning point in the Eighty Years’ War.

Meanwhile, a large part of the income for the Spanish side of the war came from trade with the East Indies. The European supply of pepper was provided solely by Portuguese fleets, and the trading post in Lisbon was no longer easily accessible to the Dutch while they were at war with Spain. Pepper was extremely valuable in those days, and the Portuguese kept their routes secret to make sure nobody else would cash in on the spice. But eventually, Dutch ships found a route to the East Indies. They sailed south, all the way around Africa, and returned with enough spices to finally make some money.

Finding a trade route to the East Indies led to the formation of the Dutch East India Company (VOC) in 1602—the first multinational corporation, and the first company to sell stock. The company did more than buy and sell spices. For several years, it had a monopoly on colonial activities in Asia, and it had the power to take prisoners and establish colonies. During its existence, the VOC boosted the economy of the Netherlands to the top of the world. This period of economic growth is referred to as the Golden Age in Dutch history.

Money may not buy happiness, but the sudden wealth of the country certainly formed the perfect environment to nurture artistic endeavors and encourage major scientific progress. These were the century and country in which Rembrandt painted The Night Watch and Antonie van Leeuwenhoek developed the microscopes with which he first observed single-celled organisms. The effects of the VOC trade have shaped entire fields of art and science, all because a few ships found a route to the East Indies in a time of economic need.

There was just one problem with the VOC trade route to the East Indies: It was quite long.

Scientific progress notwithstanding, there was no suitable way to keep the crew’s food, especially fresh fruit and vegetables, from going bad before they were even halfway there. This was a problem, because without fresh fruit, the crew was prone to scurvy. Scurvy had been the scourge of sea travelers since the fifteenth century, when ships started to sail across oceans and stayed away from home—and fruit—for too long. Starting with some spots on the skin, scurvy progressed to bleeding from mucous membranes, ulcers, seeping wounds, loss of teeth, and eventually death. Fifteenth-century explorers could lose up to 80 percent of their crew to scurvy. The solution was known and simple: eat lots of fresh fruit.

Scurvy is caused by a lack of ascorbic acid, better known as vitamin C. Our bodies use this vitamin for many metabolic processes, such as producing collagen and repairing tissue damage. Without vitamin C, we essentially slowly start to fall apart: skin breaks open, wounds won’t heal, teeth fall out.

But we humans are one of the few animals that need to eat fruit and vegetables to keep our vitamin C levels up. Most animals are quite capable of synthesizing their own vitamin C. Most, but not all. We share our need for fruit and veggies with other primates, including closely related apes as well as monkeys and tarsiers.

Our inability to synthesize vitamin C is the result of a mutation that occurred more than 40 million years ago in our shared primate ancestor, affecting the gene that encodes the L-gulonolactone oxidase (GULO) enzyme. Normally, this enzyme catalyzes a crucial step in the formation of vitamin C. But in humans and related primates the genetic mutation produces a broken enzyme. It doesn’t work, and we can’t make our own vitamin C anymore. Luckily, it’s quite easy to compensate for the lack of GULO by simply taking in vitamin C via our diets, but this also means that there was no selective pressure for a functional GULO, and we primates have been living with a broken version ever since.

The relative ease with which animals can compensate for no longer producing their own vitamin C is illustrated by the fact that the mutation that disabled our GULO enzyme millions of years ago was not the only mutation in the animal kingdom to shut down vitamin C biosynthesis. It happened at least three other times: bats, guinea pigs, and sparrows also have defective GULO enzymes and get vitamin C via their diets.

The mutation in the guinea pig’s ancestor happened more recently than ours—possibly only about 20 million years ago—but that is still far enough back to also have affected another member of the Caviidae family. The capybara also needs a steady diet of vitamin C to keep a hold on its title of largest living rodent on Earth. Especially in captivity these R.O.U.S. (rodents of unusual size) are, like the sailors and pirates of yore, at risk of scurvy unless they eat enough fresh vegetables.

Speaking of fresh vegetables, how were the VOC crew going to manage the journey to the East Indies, which took longer than the expiration date on their perishables? The ideal solution was to restock along the way, but the continent of Africa was not exactly a farmers’ market where you could just get some more fruit and veg when you needed it. Well then, they would just have to make a farmers’ market. The VOC took several Dutch farmers and settled them in South Africa to grow more food for the ships passing by along their trade route. The restocked ships could then sail on with a scurvy-free crew.

If the VOC crew had been able to make their own vitamin C, like most animals do, they wouldn’t have had to bring farmers to South Africa. That move, guided by a mutation that happened millions of years ago, entirely shaped the more recent history of South Africa. How? Here’s a hint: the Dutch word for farmer is boer.

The Boer population of South Africa were the direct descendants of the farmers relocated there to supply the VOC ships with the fruit and vegetables for their voyage to and from the East Indies. After the VOC was disbanded and British colonials settled in South Africa, the Boer population moved away from the Cape. Conflicts between the Boers and the British Empire, most notably the Second Anglo-Boer War at the end of the nineteenth century, directly led to the formation of the Union of South Africa in 1910, which was the predecessor of the current-day Republic of South Africa.

So there you have it. In a scene set by pirates, and with R.O.U.S. lurking in the background, an entire country, with all its political and cultural complications, was formed as a result of a method to distribute fruit and vegetables to the crew of seventeenth- and eighteenth-century trade ships to compensate for a genetic mutation that makes humans incapable of synthesizing their own vitamin C.

Our broken GULO enzyme may not have been able to make vitamin C for millions of years, but it’s made history just fine.

EVA AMSEN is a former biochemist who left the lab for the laptop and now spends most of her time communicating with researchers, reading about science and publishing, interviewing scientists about their hobbies, and maintaining far too many blogs. Most of Eva’s online presences can be found at http://easternblot.net.

3

SAVING ETHIOPIA’S CHURCH FORESTS

T. DELENE BEELAND

Historically, fundamentalist Christians believed mankind had a God-given right to use Earth and all its resources to meet humanity’s needs. After all, Genesis gave man dominion over Earth. In modern times, green messages of sustainability are permeating some Christian groups, yet on the whole sustainability remains more of a commitment on paper than in practice. But across the Atlantic, a much different attitude prevails. Ethiopia has the longest continuous tradition of Christianity of any African country, and followers of the Ethiopian Orthodox Tewahedo Church believe they should maintain a home for all of God’s creatures around their places of worship. The result? Forests ringing churches.

There are some 35,000 church forests in Ethiopia, ranging in size from a few acres to more than 700 acres. Some churches and their forests may date back to the fourth century, and all are remnants of Ethiopia’s historic Afromontane forests. To their followers, they are a sacred symbol of the garden of Eden—to be loved and cared for, but not worshipped.

Most church forests are concentrated in the northern reaches of the country, especially in the Lake Tana area. Here, most of the Afromontane forests have been cut down to make clearings for agriculture, pastures for livestock, and settlements. It is said that if a traveler to the area spies a forest, it surely has a church in the middle. Many also have freshwater springs.

These spiritually protected woods, also known as Coptic forests, comprise a decent chunk of the 5 percent of Ethiopia’s historical forests that are still standing. Massive deforestation has rendered these church forests true islands—green oases peppering a land laid bare.

(Courtesy of D. M. Jarzen, Ph.D.)

Connecting them to other forests is a luxury we can’t even consider, says international tropical ecologist and researcher Margaret Lowman, because the lands between them are predominantly crop fields today. Fondly known to her colleagues as Canopy Meg, Lowman is a canopy researcher who has studied forests on five continents.

What remains is fragile and isolated by habitat fragmentation. Conservationists have made these church forests a centerpiece of the country’s fight to retain its biodiversity. These beacon-like green swaths have become refuges for all kinds of species—but no one really knows what is at stake because they are extremely poorly studied.

Awakening Awareness

Alemayehu Wassie Eshete is an Ethiopian forest researcher who did his Ph.D. work on his country’s Coptic forests. His dissertation and a few related papers may form the entirety of the published scientific literature on Ethiopia’s church forests, according to Lowman.

She met Wassie at a scientific meeting a few years ago. When she asked him what he was going to do next on Coptic forests, he wept in frustration. With very limited economic means and few international connections, Wassie felt he needed help with visibility and expertise to study—and conserve—his country’s forests. Lowman began helping him, and in 2009 he invited her to visit the forests in person. She went.

With Wassie’s help, Lowman gave a PowerPoint presentation to about 100 men, mostly priests. Some had traveled for days to attend the meeting. She showed them images of their church forests.

Though some had never seen a computer, they recognized their forests, and she says they gasped audibly at the pictures showing the woods shrinking inward over time. Lowman says they intuitively grasped the value of ecosystem services because, for them, it fell under the purview of their spiritual duties to protect the biodiversity around their places of worship.

Findings from Terhi Evinen’s master’s research in forest sciences at the University of Helsinki revealed in detail how the priests conceive of their spiritual forests. What [matters to them] religiously is the number of trees, not the ecological health of the forests, Evinen wrote to me. The trees are said to be the jewelry of the church and the more trees a church has the more appreciated it is since the tree canopy prevents the prayers from being lost to the sky.

Despite this, Evinen and Lowman agree the biggest threats to these forests are not external factors such as industrial loggers or agribusiness. Rather, the biggest threat lies inside: the church members and clergy who use the forests for firewood and rely on them for livelihoods.

The clergy and church members use the wood from trees to repair their church, to make charcoal for church activities, and to make sacred utensils. Plants in the forest are eaten or used to make dyes. Deadfall is sold to congregants for cash.

The trip ingrained in Lowman’s mind that engaging the priests and church members was a vital part of studying and conserving the remaining Coptic forests.

Insightful Insects

In August 2010, Lowman returned to Ethiopia and led a team of thirteen scientists in surveying several church forests on the south shore of Lake Tana and at a rural village about sixty miles to the northeast, Debre Tabor. The purpose of the team’s trip, one hopes the first of many, was to assess the insect biodiversity and the economic importance of the tree species remaining in these sacred forests.

We didn’t even know if birds or mammals would be left in these highly threatened areas, Lowman says. We chose insects to survey because we wanted an index of something we hoped would be healthy. It would be awful to give the local people bad news right at the start. Mammals were worrisome because it may be they’ve all been hunted or poached. Birds were also problematic because the fragmentation level is so high. But also, pollinators are such an important part of ecosystem services that we thought being able to educate the local people about them at the same time would be useful.

And this embodies the heart of how Lowman has conducted her scientific career: equal parts science and public outreach.

Lowman’s team examined every level of the forests: they climbed into the canopies, shook bugs from tree limbs, and set insect traps.

They surveyed the lower reaches and scoured the forest floor where dung beetles carry out important waste-removal processes. They surveyed ants, beetles, flies, and wasps, and counted birds, mostly in the surrounding fields. The team collected in the day and during the night, rain or shine. By the end, they had gathered data on 5,500 insects, mostly from two church forests: Debresena, outside of Debre Tabor; and Zahara, close to Bahir Dar.

A month before the research trip, Lowman started a new job as the director of the Nature Research Center at the North Carolina Museum of Natural Sciences. Part of the center’s mission is to communicate science to the public and actively engage children. So she live-streamed video of the fieldwork back to the museum as a pilot project. Soon the researchers garnered the attention of local children, who watched and even helped the researchers collect their specimens. Lowman described it like this in North Carolina Naturalist: Armed with our nets and ropes and vials, we attracted a large swath of children who watched our every move and marveled at the six-legged creatures swept from the foliage. Despite the language barriers, we all laughed when ants fell on our heads, and shrieked with joy when a purple beetle appeared on the surface of our collecting tray.

When she returns next year, Lowman plans to further engage the children through educational activities to teach them about the importance of their remaining forests. Though 95 percent of their forests have been wiped off the map, the remaining church forests provide important ecosystem services. They harbor pollinator species that forests and crops require, and they sequester carbon and conserve water. Wassie estimates that 1.1 billion tons of soil is eroded in northern Ethiopia every year. The trees of the church forests help to hold a small portion of the landscape’s soil steadily in place.

Fences, Feces, and Farming

When people worship at the churches, it may be a several-hour to an all-day-long affair. Which means that people often need to relieve themselves in the forests, where there are typically no toilets. Priests and disciples also live in huts in the forest, using it for nature’s call because no other facilities